Plasticized hydrophilic colloids



Patented Nov. 21, 1950 PLASTICIZED HYDROPHILIC COLLOIDS Henry A. Molteni, Boonton, N. 5., assignor to E. F. Drew & Co., Inc., New York, N. Y., a corporation of Delaware No Drawing.

Application July 19, 1945,

Serial No. 606,029

6 Claims.

The present invention is directed to compositions containing chlorinated fatty acids and derivatives thereof and more particularly to substances of this character which are suitable as plasticizers for hydrophilic colloids and emulsions containing the same, such as proteins and carbohydrates.

In the prior art a large number of plasticizers of various types have long been known and used in connection with various materials. Among such compounds are esters of fatty acids, many of which have been found eminently suitable for various such applications. However, in certain applications it is desirable to provide a plasticizer having considerably greater plasticizing value, and this applies particularly to plasticizers for use in compositions containing aqueous or hydrophilic protein colloids. Very few plasticizers heretofore known have been found to be compatible with such colloids, and then only to a limited degree.

This invention has among the objects thereof to provide a plasticizer which is miscible with hydrophilic colloids and similar substances in relatively large proportions and which is compatible therewith organic sulphhydryl compounds, and capable of adequately plasticizing the same.

It is further among the objects of the present invention to provide a plastic composition containing a chlorinated higher fatty acid or mixtures of such acids and various derivatives thereof which are highly effective for making plastic compositions.

It is also among the objects of this invention to provide effective plasticizers for protein containing colloids of animal and vegetable origin including casein, zein and thelike.

It is still further among the objects of this invention to provide effective plasticizers for starches, degeneration products thereof, and analogous compounds.

In practicing the present invention, I take a mono-carboxylic acid having more than 5 and usually 6 to 18 carbon atoms, or mixtures of such acids as will be more fully set forth below. Such acids are chlorinated to a substantial degree from a minimum of 1 chloride atom to each molecule of acid to a maximum of 10 atoms of chlorine. The preferred range of chlorination is from 2 to 4, and preferably about 3 atoms of ch orine to the molecule. The free chlorinated acid or mixture of acids may be used directly for plasticizing of various substances. Among such compounds, there may be used chlorinated compounds of caproic, enanthic, caprylic, pelargonic, capric, lauric, myristic, palmitic, oleic, and stearic acids.

The following are specific examples of the operation of the present invention.

Example I There is provided a mixture of fatty acids in approximately the following proportions:

Per cent Laurie acid 63 Myristic acid 25 Palmitic acid 12 Such a mixture of acids may be obtained by splitting of coconut oil by a Twitchell reagent to give a mixture of fatty acids and small amounts of residual glycerides, and then fractionally distilling, or it may be obtained by acidulating coconut foots, which is a mixture of coconut soaps and oil, giving a mixture of fatty acids and oil which may then be treated with a Twitchell agent as above to split the oil, followed by subsequent fractional distillation. The lower boiling fraction may be removed by fractional distillation and the residual mixture of higher fatty acids may contain up to 8 to 10% of fatty acids esterified with glycerine. The specific compositions set forth above may contain also lesser amounts of higher and lower fatty acids. The composition set forth has a free fatty acid value of 116 calculated as oleic acid, a saponification value of 256, and an iodine value of 15.

The charge is placed in a glass lined reaction vessel and dry gaseous chlorine is passed into the same with continuous stirring. Chlorine is fed to the reaction vessel continuously and as the reaction proceeds, the temperature rises to about C. Chlorination is continued at about this temperature until the free fatty acid value of the product has fallen to 80.9. Air is blown through the reactive mass to remove any hydrogen chloride dissolved therein. The resulting product contained 25% of chlorine by analysis and it was a viscous light amber-colored oil having a specific gravity of 1.11 and a refractive index of 1.48 (n The product had approximately 2.4 atoms of chlorine to the molecule.

Example II The lower boiling fraction of the coconut fatty acids as described in Example I, and consisting of the distillate from the above stated fractionation, may have the following composition:

Per cent Caprylic acid 54 Capric acid 40 Caproic acid 6 This mixture of fatty acids may contain lesser amounts of some of the higher fatty acids of coconut oil.

The mixture of acids is placed in a glass lined kettle, together with 0.3% lauroyl chloride as a catalyst. Chlorination is caused to take place, as in Example 1, the temperature rising to 120 to 140 C., the chlorination being continued until the free fatty acid value has fallen to 118.6, indicating a molecular weight of 238 and the introduction of 2.4 atoms of chlorine into each fatty acid molecule. The product is purified by washing, drying and filtering.

Example III Coconut oil is hydrolyzed and the free fatty acids distilled substantially completely so as to obtain a mixtureof substantially all of the fatty acids present in the original oil and in approximately the same proportions,

To the mixed fattyacids in a glass lined kettle is added (3.3% of lauroyl chloride, and subjected to the action of chlorine, the temperature rising to about 140 to 160C. Chlorination is continued until the free fatty acid value has fallen to 75.5. Theaverage molecular weight of the product was S'Ieand it indicated therewas present 4.8 chlorine atoms for each fatty acid molecule. The product was a very viscous oil and was washed with water to dissolve out any free hydrogen chloride present.

Example IV The mixture of fatty acids and glycerides thereof described in Example I is subjected to fractional distillation. The distilled fatty acids are substantially freefrom glyceride esters, and are chlorinated as set forth in Example I.

The products are eminently suitable for'incorporation with such hydrophylic colloids as casein, zein, hordein, soybean protein, glue, gelatine, egg albumin, silk, keratin, wool, hair, as well as nonprotein colloids, su ch as agar, tragacanth, gum arab-ic, methyl-cellulose, starch, dextrin, and flour, called hydrophilic in the claims.

A number of plasticized compositions were made by mixing equal weights of a colloid such as zein and the plasticizers of the specific examples. The mixture was accomplished by stirring it at about 150 C. to cause mutual solution of the constituents. Excellent plasticizing efiects were obtained with the free acids of Examples I, II and III.

In another series of tests, 40 parts of plasticizer were added to 100 parts of zein, with the use of 150 parts of ethyl alcohol as a solvent. After thorough mixing and solution, films were deposited therefrom and examined. In the case of the esters of the chlorinated fatty acids, there was in some instances a slight cloudiness in the solution and film. However, in those compositions using the free chlorinated acids, all solutions and films were clear.

It has been found that the compositions of Examples I and II particularly give'exceptionally good plasticizing action in such hydrophilic colloids as are principally protein in character, of which casein and zein are common examples. Such plasticizers impart to these proteins excellent water resistance, good flexibility and render the composition tough. Also, such compositions are stable at various humidities. There is no tendency of the formation of cheesiness in the compositions. This permits the productionof superior coatings for paper, leather, and textiles, stronger and more water-resistant glues and adhesives, more stable and weather resistant paints, plastics and fiber products. These same considerations hold true in general for zein, soybean protein, hordein, and the other aqueous colloids.

As'an example of the excellent properties of a casein mixture, there has been provided a composition consisting of 100 parts of casein, 15 parts of borax and 500 parts of water, the constituents being heated to form a solution. To this is added 50 parts of the product of Example I, the whole stirred until uniform, and films cast therefrom. When dry the films are clear, flexible, tough and strong, having improved water resistance and high stability at high and low humidities.

Another example of the use of the plasticizer with casein is as follows: 10 parts of casein are stirred 'into 50 parts of water and 3, 'parts of a concentrated aqueous solution of ammonia (28% ammonia) added. The mixture is agitated at -95 C. and mparts of plasticizer prepared by the method described in Example I is added. Agitation is continued for 30 minutes at C. When this preparation is applied to =paper acoating is obtained that'is superior in many respects to the coating prepared in the same manner, except that 10 parts'of water aroused in place of 10 parts of plasticizer. The-coatingthat'contained plasticizer has higher glossfgreater flexibility and is more water repellant. The coating that contains plasticizer gives 'more uniform application.

An example of the 'use'of the plasticizer with zein is: 7 parts of zein'are mixed with 15 parts of ethanol and 1 parts of 'a plasticizer, prepared according to example I, added. Paper is coated with this mixture and paper is coated with a similar mixture in which 7 parts of ethanol is substituted for the plasticizer. The coating that contained plasticizer'is more flexible, more water repellent 'and more uniform than the coating without-plasticizer.

In another example, 10 parts of zei n and 5 parts of sulfonated castor oil are mixed with 50 parts of water. "Sixpar ts of aqueous ammonia (28% ammonia) are added, mixed and ll) parts of plasticizer, prepared according to Example I, are added. Paper is coatedfwith this mixture and compared Jwithpaper that had been coated with a similarmixture'in whichilil parts of water had been substituted for the 10 parts of 'plasticizer. The coatings containing plasticizer are much more glossyand morewate'r repellent than the coatings without plasticizer.

An example of the 'use of the plasticizer with starch is: 15 parts ofthick boiling cornstarch are mixed with 300p'arts'of water and agitated on'a steam bath until the starch is gela tinized. 15 parts of a plasticizer,prepared according to Example Lareadded to the mix. When this mix is appliedto paper a coating'is'obtained that has greater flexibility'than when starch is used without pastimes In addition the paper is made more easily wettabla'thus improving its ability to accept water color or aqueous inks. Another advantage that'is realized "by the use of the plasticizeristhat the viscosity of the starch size is increased,thus permitting the application of the'size-to paper with considerably less penetration of the-size into the paper.

Although the invention has been described by the use of a number of specific examples, such examples are'intended to be illustrative-andnot to limit' the invention. It'will be obvious to those skilled in the art that many changesinthe details of the practice of the invention may be made within the spirit thereof. For instance, the proportion of plasticizer may be varied over a wide range, although usually the amount of plasticizer is less than 50% of the substances being plasticized. The plasticizer may be used in conjunction with other hydrophilic colloids than those named above and may be used in admixture with other plasticizers. The ratio of the fatty acids in the mixture of chlorinated fatty acids may vary considerably, as for example, the caprylic acid mixtures may contain from 50 to 99% of caprylic acid. Fatty acids derived from other oils than coconut oil may be used and synthetic fatty acids or acids obtained from other sources are equally suitable. The conditions of the reactions may be changed, as for example, other proportions, time of treatment, temperatures of reaction and the like may be changed as is well-known.

These and other changes may be made in the details of the invention, which is to be broadly construed and not to be limited except by the character of the claims appended hereto.

I claim:

1. A hydrophilic colloid taken from the class consisting of the protein and carbohydrate colloids, having incorporated therein a free fatty acid having at least 6 carbon atoms chlorinated with at least 2 atoms of chlorine in an amount sufiicient to plasticize said colloid.

2. A hydrophilic colloid taken from the class consisting of the protein and carbohydrate colloids, having incorporated therein a free fatty acid having at least 6 carbon atoms chlorinated with from 2 to 4 atoms of chlorine in an amount sufficient to plasticize said colloid.

3. A hydrophilic colloid taken from the class consisting of the protein and carbohydrate colloids, having incorporated therein a free fatty acid having at least 6 carbon atoms chlorinated with about 3 atoms of chlorine in an amount sufiicient to plasticize said colloid.

'4. A hydrophilic colloid taken from the class consisting of the protein and carbohydrate colloids, having incorporated therein a mixture of fatty acids having 6 to 10 carbon atoms chlorinated with at least 2 atoms of chlorine in an amount sufiicient to plasticize said colloid.

5. A hydrophilic colloid taken from the class consisting of the protein and carbohydrate colloids, having incorporated therein a mixture of fatty acids having 12 to 18 carbon atoms chlorinated with at least 2 atoms of chlorine in an amount suficient to plasticize said colloid.

6. A hydrophilic colloid taken from the class consisting of the protein and carbohydrate colloids, having incorporated therein a mixture of fatty acids having 6 to 18 carbon atoms chlorinated with from 2 to 4 atoms of chlorine in an amount sufficient to plasticize said colloid.

HENRY A. MOLTENI.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,094,830 Aylsworth Apr. 28, 1914 2,158,481 Hansen May 16, 1939 2,233,891 Kratz Mar. 4, 1941 2,255,230 Ross et a1 Sept. 9, 1941 2,269,990 SaffOrd Jan. 13, 1942 2,332,849 Gruber Oct. 26, 1943 2,345,006 Ross et a1. Mar. 28, 1944 2,386,534 Barsky Oct. 9, 1945 2,392,100 Price et a1 Jan. 1, 1946 

1. A HYDROPHILIC COLLOID TAKEN FROM THE CLASS CONSISTING OF THE PROTEIN AND CARBOHYDRATE COLLOIDS, HAVING INCORPORATED THEREIN A FREE FATTY ACID HAVING AT LEAST 6 CARBON ATOMS CHLORINATED WITH AT LEAST 2 ATOMS OF CHLORINE IN AN AMOUNT SUFFICIENT TO PLASTICIZE SAID COLLOID. 